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HackWithInfy• Prep

Minimum Jumps to Reach End via Prime Teleportation

Difficulty
Medium
Acceptance Rate
31.8%

Problem Statement

You are given an integer array nums of length n.

You start at index 0, and your goal is to reach index n - 1.

From any index i, you may perform one of the following operations:

  • Adjacent Step: Jump to index i + 1 or i - 1, if the index is within bounds.
  • Prime Teleportation: If nums[i] is a prime number p, you may instantly jump to any index j != i such that nums[j] % p == 0.

Return the minimum number of jumps required to reach index n - 1.

 

Example 1:

Input: nums = [1,2,4,6]

Output: 2

Explanation:

One optimal sequence of jumps is:

  • Start at index i = 0. Take an adjacent step to index 1.
  • At index i = 1, nums[1] = 2 is a prime number. Therefore, we teleport to index i = 3 as nums[3] = 6 is divisible by 2.

Thus, the answer is 2.

Example 2:

Input: nums = [2,3,4,7,9]

Output: 2

Explanation:

One optimal sequence of jumps is:

  • Start at index i = 0. Take an adjacent step to index i = 1.
  • At index i = 1, nums[1] = 3 is a prime number. Therefore, we teleport to index i = 4 since nums[4] = 9 is divisible by 3.

Thus, the answer is 2.

Example 3:

Input: nums = [4,6,5,8]

Output: 3

Explanation:

  • Since no teleportation is possible, we move through 0 → 1 → 2 → 3. Thus, the answer is 3.

 

Constraints:

  • 1 <= n == nums.length <= 105
  • 1 <= nums[i] <= 106